MBLab 1.7.4 add on refuses to install in Blender 2.8 Beta?
I had the same issue, and by looking carefully at the log I figured it out.

This is how I solved it:

Install the addon as usual.

In my case, I had it already installed but wasn't showing up in the addon list.

You have to do the "renaming thing" but instead of just renaming the installation ZIP, you have to rename the addon folder that is installed in:

/home/"user name"/.config/blender/2.8/scripts/addons

I renamed it to just MBlab, and that was it. I hope it works for you as well, have a nice day.